On Fri, Aug 03, 2007 at 02:05:53PM +1000, Keith Owens wrote:
None of this should be in any way user selectable.
We are currently having problems although distributions ship with
4k stacks. Any option offering less than the default distributions
ship with, in the worst case hidden under EMBEEDED, could be called
CONFIG_NONWORKING_KERNEL since it will be an untested configuration that
will no longer be working after some time.
Even with the current stack usage in the kernel the threshold value must
be at a value that you can't do this with only 4 kB of initial stack
since you'd have to use extra stack when you have 3 kB left.
Consider that the highest stack usage of a single function of a network
device driver (sic) is currently over 2 kB. 
And since relaxed stack usage rules will result in driver authors
becoming more sloppy, only 3 kB of free stack won't always be enough...
"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed